chr3-15644671-G-A

Variant summary

Our verdict is Pathogenic. The variant received 18 ACMG points: 18P and 0B. PVS1PM2PP5_Very_Strong

The NM_001370658.1(BTD):​c.755G>A​(p.Trp252*) variant causes a stop gained change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000248 in 1,614,000 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★★).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000021 ( 0 hom. )

Consequence

BTD
NM_001370658.1 stop_gained

Scores

5
1
1

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:2

Conservation

PhyloP100: 10.0

Publications

0 publications found
Variant links:
Genes affected
BTD (HGNC:1122): (biotinidase) The protein encoded by this gene functions to recycle protein-bound biotin by cleaving biocytin (biotin-epsilon-lysine), a normal product of carboxylase degradation, resulting in regeneration of free biotin. The encoded protein has also been shown to have biotinyl transferase activity. Mutations in this gene are associated with biotinidase deficiency. Multiple transcript variants encoding different isoforms have been described. [provided by RefSeq, Aug 2013]
BTD Gene-Disease associations (from GenCC):
  • biotinidase deficiency
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Myriad Women’s Health, ClinGen, Orphanet, Ambry Genetics, G2P, Labcorp Genetics (formerly Invitae)
  • Leigh syndrome
    Inheritance: AR Classification: MODERATE Submitted by: ClinGen

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 18 ACMG points.

PVS1
Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most exon, not predicted to undergo nonsense mediated mRNA decay. There are 134 pathogenic variants in the truncated region.
PM2
Very rare variant in population databases, with high coverage;
PP5
Variant 3-15644671-G-A is Pathogenic according to our data. Variant chr3-15644671-G-A is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 2445709.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
BTDNM_001370658.1 linkc.755G>A p.Trp252* stop_gained Exon 4 of 4 ENST00000643237.3 NP_001357587.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
BTDENST00000643237.3 linkc.755G>A p.Trp252* stop_gained Exon 4 of 4 NM_001370658.1 ENSP00000495254.2

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152108
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD4 exome
AF:
0.00000205
AC:
3
AN:
1461892
Hom.:
0
Cov.:
31
AF XY:
0.00000138
AC XY:
1
AN XY:
727248
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53418
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00000270
AC:
3
AN:
1112012
Other (OTH)
AF:
0.00
AC:
0
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.508
Heterozygous variant carriers
0
1
1
2
2
3
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.00000657
AC:
1
AN:
152108
Hom.:
0
Cov.:
32
AF XY:
0.0000135
AC XY:
1
AN XY:
74302
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41410
American (AMR)
AF:
0.00
AC:
0
AN:
15264
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3468
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5196
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4820
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10606
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68028
Other (OTH)
AF:
0.00
AC:
0
AN:
2090
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.475
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.00000378
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000116
AC:
1

ClinVar

Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:2
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Biotinidase deficiency Pathogenic:2
Sep 02, 2023
Baylor Genetics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Feb 04, 2023
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: BTD c.755G>A (p.Trp252X) results in a premature termination codon and is predicted to cause a truncation of the encoded protein, which is a commonly known mechanisms for disease. This variant is predicted to disrupt the last 272 amino acids in the protein sequence. Truncations downstream of this position have been classified as pathogenic within ClinVar (e.g. c.873del [p.Ser291fs], c.1025T>A [p.Leu342Ter]). The variant was absent in 251444 control chromosomes (gnomAD). c.755G>A has been reported in the literature in at least one compound heterozygous individual affected with Biotinidase Deficiency (Procter_2016). These data do not allow any conclusion about variant significance. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014. Based on the evidence outlined above, the variant was classified as likely pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_addAF
Pathogenic
0.63
D
BayesDel_noAF
Pathogenic
0.66
CADD
Pathogenic
40
DANN
Uncertain
1.0
Eigen
Pathogenic
1.0
Eigen_PC
Pathogenic
0.93
FATHMM_MKL
Pathogenic
1.0
D
PhyloP100
10
Vest4
0.77, 0.83, 0.84
GERP RS
5.8
Mutation Taster
=0/200
disease causing

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.0
Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

Other links and lift over

dbSNP: rs148031701; hg19: chr3-15686178; API